Running in advice

[BMWChris]

Engine (1500 Triumph in Competition Midget) should have been rebuilt by now - balanced bottom end, rebore, expensive bearings, new pistons and camshaft etc). Its going to take a while to get it back in set-up on the rolling road. I'm getting conflicting advice on running in. Some say take it gently for 3000 miles (more than I did all last year) other say to go for it from the outset.

Should I run it in before the rolling road? (not keen as I'm worried about pre ignition damaging it again - this was what lead to the rebuild)

How much running in will it need before used in competition? Standard cam so won't rev over 6000 at best.

[jlh]

Definately run the engine in for atleast 500-1000 miles before putting it on the rollers. Get a safe set up on the engine ignition and fuel wise then run the engine in for 500 miles, with running in oil. Drop the oil and filter and replace with the correct oil add a further 500 miles increasing the rpm limit. The main thing to remember to not to labour the engine or sustain high rpm for long periods.
The rolling roadf is very hard on engines so you need it fully run in before trying a set up.
Hope this helps.


Jonathon

[lowdrag]

I agree with Jonathon since my E-type engine I ran in for 2,500 as recommended and it has run impeccably for 80,000 miles. In the days the Spitfire was built there was always a recommended running in period (we used to cut the rear window sticker to read "ruining") which was 1,000 miles. In other words, Jonathon has got it absolutely right - as usual.

[dellow]

on first start up you should run the engine at about 2000rpm for 20 mins, to let the camshaft bed in, NOT IDLE, if you don't you run the risk of knackering your cam, there should have been instructions like this in the box with the camshaft.

Edited by dellow on Monday 26th April 23:46

[a8hex]

The other advice I was given with my engine was not to constantly sit at the same revs either while running in, keep varying the speed a bit.
Conrods flex, if you run at a constant engine speed then they always end at the same point and you tend to introduce a step there in the lining.
Not a problem with normal road driving, but if you decide to run in on a Motorway or other long fast road it could be a problem.

[chard]

Try this.

http://www.pumaracing.co.uk/runin.htm

[//j17]

From the sounds of it this isn't a DIY rebuild so, if the engine builder is worth their salt they will tell you how to run it in.

Failing that the following is the running in instructions I had from my (Triumph specialist) engine builder for a fast road engine.

First 3000 Miles

---

Start keeping the RPM below 3000, slowly using more and more through to 5000 by end of 3000 miles.
DON'T let the engine labour at low RPM.
Avoid holding constant RPM for any significant period. Keep the tacho needle moving.

At 3000 Miles

---

Change oil.
Change oil filter.
Re-torque cylinder head (in tightening order back each nut of a 1/4 turn then re-torque progressively).

Post 3000 Miles

---

Book rolling road session to get carbs re-jetted/needled depending on carbs. or re-mapped if running EFi.
Drive it like you stole it and enjoy.

[onomatopoeia]

//j17 said:

From the sounds of it this isn't a DIY rebuild so, if the engine builder is worth their salt they will tell you how to run it in.

This. When I had the previous (Imp) engine in the Davrian rebuilt the engine builder told me to give it full beans from the start and that I'd feel it loosen up after the first run. He also told me what oil I should use (Castrol R40)

Doing 500 miles of running in on a car with no lights, slick tyres and so on is challenge, as are low revs when it doesn't come on cam until over 5000 .

[BMWChris]

Going to have to get as far over 500 miles as I can before going for it but…

Car needs engine back in, a few little jobs that can't be done till engine in and MOT so car not realistically going to be back on the road until 19th.

First event on Thurs 27th but that is local autotest so I could miss it or possibly use my other car just to get some points on the board.

First proper event is a rally down in Kent on 30th May - mostly road miles (over 400 by the time we've got there and back). Realistically going to be very hard not to use maximum attack on the tests.

Sprint at Silverstone (on new circuit – very excited!) on the 6th June - must be able to use max attack by then. That way I’ll be going faster when I get lost and crash!

So my aim is to get it on the RR somewhere around the 26th. This could mean me spending several evenings lapping the ring road!

[a8hex]

BMWChris said:

So my aim is to get it on the RR somewhere around the 26th. This could mean me spending several evenings lapping the ring road!

Because of the need to put miles on quickly I did most of my running in up and down the M4, just keep varying the speed and loading on the engine.